Approaches to produce and characterize recombinant protein VP1-2A of HAV for serological rapid test application.

Studies reporting the expression of hepatitis A virus (HAV) structural proteins, specifically recombinant VP1-2A containing an immunogenic activity, use the Escherichia coli system. Recombinant HAV proteins may represent a source of less expensive antigens for application in different diagnostic platforms. However, the formation of insoluble aggregates is an obstacle to obtaining large amounts of HAV proteins in their native form. To overcome this obstacle, some approaches were applied in this study to improve purification, solubility, and protein expression levels. Critical properties were evaluated. The introduction of another insertion codon to increase the protein concentration and vector activity was observed and verified by SDS-PAGE. The expression was established with 0.4 mM IPTG for 4 h at 37 °C. The VP1 protein was partially soluble at an isoeletric point (pI) of 6.45. The majority of HAV VP1-2A proteins measured 45.19 kDa in size and had a homogeneity of 53.58%. Multi-antigen print immunoassay (MAPIA) showed antigenicity at different HAV VP1-2A concentrations, and microsphere-based immunoassays showed a specificity of 100% and a sensitivity of 84%. HAV VP1-2A was characterized using different sensitivity methods to prove its biological activity, indicating its use as a tool for the diagnosis of Hepatitis A virus infection.

Successful treatment of prolonged cholestasis following hepatitis A infection in a child with oral steroid therapy.

Hepatitis A is a common cause of acute infectious hepatitis in children, transmitted through the faeco-oral route. Although mostly self-limiting, cholestasis is a rare but known complication of acute hepatitis A in children. This report presents an adolescent girl who developed cholestatic features following hepatitis A infection and successful treatment with oral steroid therapy. Prolonged cholestasis jaundice (PCJ) is a known manifestation of hepatitis A infection, characterised by prolonged fever, pruritus and jaundice. While the exact mechanisms causing PCJ are not fully understood, immunological-mediated responses could play a role. Treatment options for PCJ are limited, and there is no currently accepted standard of care. Steroids have shown promise in treating PCJ, as observed in this case and a few other reported cases. When other therapies fail to alleviate symptoms, corticosteroids should be considered as a potential treatment option. However, further studies are required to conclusively establish their efficacy.

Development of a cell-free toehold switch for hepatitis A virus type I on-site detection.

Picornavirus hepatitis A virus (HAV) is a common cause of hepatitis worldwide. It is spread primarily through contaminated food and water or person-to-person contact. HAV I has been identified as the most common type of human HAV infection. Here, we have developed a cell-free toehold switch sensor for HAV I detection. We screened 10 suitable toehold switch sequences using NUPACK software, and the VP1 gene was used as the target gene. The optimal toehold switch sequence was selected by in vivo expression. The best toehold switch concentration was further found to be 20 nM in a cell-free system. 5 nM trigger RNA activated the toehold switch to generate visible green fluorescence. The minimum detection concentration decreased to 1 pM once combined with NASBA. HAV I trigger RNA could be detected accurately with excellent specificity. In addition, the cell-free toehold switch sensor was verified in HAV I entities. The successful construction of the cell-free toehold switch sensor provided a convenient, rapid, and accurate method for HAV I on-site detection, especially in developing countries, without the involvement of expensive facilities and additional professional operators.

Acute liver failure due to hepatitis A virus presented with Guillain-Barré syndrome and ocular myasthenia gravis.

Hepatitis A is one of the most common causes of acute viral hepatitis in children. Immunological manifestations involving the nervous system are rare with hepatitis A infection. We report a case of a toddler who presented with acute liver failure secondary to hepatitis A infection. The child showed clinical and laboratory improvement initially with conservative management. However, after the initial improvement, she developed acute-onset ptosis along with areflexia. Serological and neurophysiological tests revealed the occurrence of ocular variant Guillain-Barré syndrome and ocular myasthenia gravis, which was only partially responsive to treatment (intravenous immunoglobulin and pyridostigmine). A sudden clinical deterioration was noted after the onset of ptosis. She succumbed on day 40 of hospitalisation due to hospital-acquired infection along with the primary hepatic pathology. This is a rare coincidental presentation of acute viral hepatitis A infection with autoimmune manifestations.

Severe acute hepatitis of unknown etiology in a large cohort of children.

BACKGROUND: We evaluated the proportion, clinical features, and outcomes of previously healthy children presenting to a large Canadian quaternary pediatric center with severe acute hepatitis of unknown etiology. METHODS: All patients with serum alanine aminotransferase (ALT) > 500 U/L or aspartate aminotransferase (AST) > 500 U/L between June 1, 2018, and May 31, 2022, at The Hospital for Sick Children, were identified. Subjects with only AST > 500 U/L were excluded. Clinical characteristics, investigations, and outcomes for patients without clear etiology for ALT > 500 U/L (severe acute hepatitis of unknown etiology) for our study period and from October 1 to May 31 of each year 2018-2021 were reviewed. RESULTS: Of 977 patients with ALT/AST> 500 U/L, 720 had only ALT > 500 U/L. We excluded age below 6 months (n = 99) or above 16 years (n = 66), known pre-existing liver conditions (n = 66), and ALT > 500 U/L in already admitted patients (n = 151). Among the remaining 338 children with ALT > 500 U/L at presentation, an etiology was identified in 303 subjects. 33 (9.8%) children [median age 6.1 y (range 0.5-15.5); 61% male] were confirmed as severe acute hepatitis of unknown etiology. Twenty patients (60.6%) were tested for blood adenovirus by PCR, and 1 (5%) was positive (serotype B7). Liver tissue specimens from 18 patients revealed no evidence of viral inclusions or adenovirus. Twelve (36.3%) presented with pediatric acute liver failure, with 8 (24.2%) requiring liver transplantation. There were no deaths. Hepatitis-associated aplastic anemia occurred in 5 (15%) patients. CONCLUSIONS: Of children presenting with severe acute hepatitis to a quaternary children's hospital over a 48-month period, 9.8% had unknown etiology with no change over time. Liver transplantation remains an important treatment strategy for those presenting with pediatric acute liver failure phenotype. The frequency of cases associated with human adenovirus infection was noncontributory.

Molecular diagnosis of patients with hepatitis A virus infection using amplicon-based nanopore sequencing.

High-throughput sequencing is a robust tool used for identifying and tracking pathogen outbreaks. Whole-genome sequencing of hepatitis A virus (HAV) remains poor due to ultra-low viral loads, limitations of next-generation sequencing technology, and its high costs in clinical applications. This study evaluated multiplex polymerase chain reaction (PCR)-based nanopore sequencing to obtain whole-genome sequences of HAV. The HAV genomes were obtained directly from patient specimens for a rapid molecular diagnosis of viral genotypes. Serum and stool samples were collected from six patients with hepatitis A infection. Amplicon-based nanopore sequencing was performed from the clinical specimens to identify HAV genotypes by acquiring nearly complete-genome sequences. TaqMan-based quantitative PCR (qPCR) was conducted to detect and quantify multiple HAV genes. Singleplex-based nanopore sequencing demonstrated high genome coverage rates (90.4-99.5%) of HAV within 8 h, at viral RNA loads of 10 to 105 copies/µL. TaqMan qPCR showed multiplex quantification of HAV genes namely, VP0, VP3, and 3C. This study provides useful insights into rapid molecular diagnosis during hepatitis A outbreaks and may ultimately augment public health disease surveillance in the hospital and epidemiology field.

Sporadic Hepatitis A Virus PCR False-Positive Results Observed during Reflex Testing of Serum Samples Previously Tested for Anti-HAV Antibodies and Caused by Contamination with HAV RNA Present in the Reagents of the Commercial Anti-HAV Immunoassay.

Hepatitis A diagnosis relies on serology and occasionally on hepatitis A virus (HAV) RNA detection. For timely diagnosis and the avoidance of drawing additional blood, molecular testing is often performed as reflex testing by using blood specimens that were initially sent for anti-HAV serology. Reflex molecular testing is preferably performed from different sample aliquots, but, for limited sample quantities, it uses samples that have been preprocessed in an immunoassay analyzer. In 2012, we first observed sporadic HAV RNA-positive cases that were inconsistent with patients' serological profiles and/or medical histories, suggesting that occasional laboratory contamination was causing false-positive PCR results. Multiple external quality assurance (EQA) and laboratory surface contamination checks were performed, questionable specimens were tested with various HAV RNA tests, and follow-up serum/stool samples were collected. All contamination-check samples and samples from healthy individuals tested HAV RNA-negative, and the laboratory successfully passed all EQAs. The HAV RNA-positive results were reproducible with various HAV RNA assays. No patients seroconverted, and their follow-up samples were consistently HAV RNA-negative. Finally, a detailed review of testing protocols revealed a correlation between HAV RNA false positivity and preceding anti-HAV testing with the Cobas-e411 automated immunoassay analyzer. HAV RNA was detected in the Cobas-e411 anti-HAV reagents, with the HAV sequences matching those from the false-positive samples. Preceding anti-HAV testing using two other immunoassay analyzers did not result in subsequent HAV RNA false positivity during reflex testing. The Cobas-e411 pipetting procedure with a single pipette tip collecting samples and anti-HAV reagents contaminated the original sample with the HAV RNA that was present in the immunoassay's reagents, thereby resulting in HAV RNA false positivity during the reflex testing. IMPORTANCE We present the first report of sporadic HAV PCR false-positive results that have been observed during the reflex testing of serum samples that have previously been tested for anti-HAV antibodies and have been caused by contamination with HAV RNA that is present in the reagents of the commercial anti-HAV immunoassay, with potentially serious clinical consequences. Although HAV RNA was consistently detected in the anti-HAV reagents of all three automated immunoassay analyzers that were in use in our laboratory, only the use of one analyzer and the corresponding commercial anti-HAV immunoassay reagents resulted in contamination that led to false positive HAV RNA results, and this was due to a peculiar pipetting mode of action in which the analyzer uses a single pipette tip to collect both anti-HAV reagents and a sample, which consequently causes the permanent contamination of the original sample with HAV RNA. Manufacturers should strongly consider the occasional need for reflex molecular testing from preprocessed samples and design their analyzers in a way that prevents contamination.

Focal Segmental Glomerulosclerosis Followed by Acute Hepatitis A Infection: Case Report.

Background and Objectives: Chronic viral hepatitis such as hepatitis B or hepatitis C is frequently related to nephropathies, yet acute hepatitis A virus (HAV) infection is an exception. Materials and Methods: A 43-year-old male presented with jaundice accompanied by nausea and vomiting. The patient was diagnosed with acute HAV infection. Although the liver function improved after conservative treatment, various symptoms such as proteinuria, hypoalbuminemia, generalized edema and pleural effusion persisted. Due to nephrotic syndrome, the patient was referred to the clinic of the nephrology department and a renal biopsy was performed. Results: The result of the renal biopsy was focal segmental glomerulosclerosis (FSGS) based on histology, electron microscopy and immunohistochemistry. Therefore, based on the clinical history and biopsy results, the patient was diagnosed as having FSGS aggravated by acute HAV infection. Proteinuria, hypoalbuminemia and generalized edema were improved after prednisolone treatment. Conclusions: Although less common, acute HAV infection can also present with an extrahepatic manifestation, for example, FSGS. Hence, clinical attention is required if proteinuria or hypoalbuminemia persists in patients with acute HAV infection.

Spectrum of viral hepatitis in hospitalized children in western India.

Viral hepatitis is a major public health problem affecting children globally. Clinical presentation varies from asymptomatic illness to hepatitis, and liver failure. Data on clinical features and laboratory parameters were collected and analysed on 300 children, aged 1-12 years, admitted with confirmed viral hepatitis. A small majority (52%) were boys. The mean age of presentation was 6.9 ± 2.8 years with the commonest symptoms being anorexia or vomiting (in 98%), fever (in 89%) and jaundice (in 71.3%). Tender hepatomegaly was seen in 31.7%. Almost all (97.6%) had hepatitis A, though mixed infection (A & E) was seen in 1.7%. Only 8% had serum bilirubin levels >200 µmol/L. Significantly elevated (>20 µkat/L) levels of aspartate transaminase and alanine transaminase were seen in 19% and 25.3% of cases respectively. Coagulopathy (PT >15 s) was present in 11.0% cases. HAV remains the most common cause of viral hepatitis in children in our environment. Public awareness and universal vaccination should be the focus to prevent morbidity and mortality due to these pathogens.

A custom hepatitis A virus assay for whole-genome sequencing.

Since 2016, the United States has experienced a resurgence in the number of hepatitis A virus (HAV) cases and outbreaks. These outbreaks have been sustained by person-to-person transmission with cases occurring predominantly in high-risk populations including intravenous drug users, individuals experiencing homelessness, and men who have sex with men. To investigate HAV transmission, a molecular-surveillance system consisting of real-time RT-PCR (rRT-PCR) for detection, and a conventional RT-PCR assay for genotyping of HAV, was established in New York State (NYS) in 2019. Since then, a total of 271 HAV-positive serum samples collected from cases across NYS between 2019 and 2021 were identified by rRT-PCR. To rapidly and efficiently generate HAV whole-genome sequences, a custom AmpliSeq™ panel was designed in collaboration with Thermo Fisher. To streamline the process, sample preparation was performed on an Ion Chef and sequencing on an Ion S5XL. Of the 271 HAV-positive samples, the whole-genome sequencing (WGS) assay successfully generated 134 near-complete, high-quality HAV sequences. Phylogenetic analysis of the VP1-2A region identified 216 IB, 48 IA, and 2 IIIA genotypes, while 5 were unable to be typed due to poor sequence in this key region. The HAV whole-genome sequencing approach provided a more efficient and streamlined approach for genotyping HAV compared to previous methods and resulted in phylogenetic trees with enhanced resolution compared to the HAV VP1-2A region alone.

Assay Sensitivity Difference Can Induce Anti-Hepatitis A Virus IgM Non-Reactive But Total (IgM and IgG) Reactive Results in Early Acute Hepatitis A.

Although anti-hepatitis A virus (HAV) IgM non-reactive and anti-HAV total (immunoglobulin [Ig] M and IgG) reactive results are generally interpreted as immunity to HAV, some early acute hepatitis A patients show the same results. We compared IgM detection sensitivity between anti-HAV IgM and anti-HAV total assays. Acute hepatitis A patients' samples were serially diluted and tested with Elecsys anti-HAV IgM and total assay (Roche Diagnostics). This resulted in anti-HAV IgM non-reactive but anti-HAV total reactive results. Samples of two hepatitis A patients showing false-negative anti-HAV IgM at initial presentation were analyzed with Elecsys, Atellica (Siemens Healthineers), and Alinity (Abbott Laboratories) HAV assays. Elecsys, Atellica, and Alinity anti-HAV IgM converted reactive on hospital day 3, whereas Elecsys and Atellica anti-HAV total results were reactive from hospital day 1. The anti-HAV total assay had higher sensitivity in detecting IgM antibodies than the anti-HAV IgM assay.

Pleural Effusion: An Uncommon Manifestation of Hepatitis.

Hepatitis A virus infection is the commonest form of hepatitis in pediatric age group and common health problem in developing countries due to poor sanitation. The clinical spectrum of hepatitis A virus infection ranges from asymptomatic infection to fulminant hepatitis and the symptoms are primarily hepatobiliary or constitutional. Here, we present a case of 16 years old male who presented with complains of fever, vomiting, anorexia, right sided abdominal pain, shortness of breath and cough. On clinical examination, patient has hepatomegaly and decreased breath sounds on right sided mammary, infra- mammary and infra scapular region. Blood investigations showed aminotransferases while pleural effusion and ascites with thickened gall bladder were found in chest x-ray and abdominal ultrasonography respectively. In absence of others causes, pleural effusion can be a rare complication of hepatitis A. Thus, this complication should be kept in mind in endemic countries in clinically matching scenarios. Keywords: Acalculous cholecystitis; ascites; hepatitis A; pleural effusion.

Improving the accuracy of clinical interpretation of serological testing for the diagnosis of acute hepatitis a infection.

BACKGROUND: Hepatitis A (HA) remains a common infection globally that results in a self-limiting hepatitis with gastrointestinal and systemic symptoms. Direct detection of the virus in blood or stool is often not possible once symptomatic. Serological testing is frequently performed to investigate abnormal liver function tests - and interpretation of equivocal and low-level positive anti-hepatitis A virus (HAV) IgM is difficult even in the context of accurate epidemiological and clinical information. OBJECTIVES: The aim of this project was to characterise the association between low-level reactive anti-HAV IgM results and clinical disease. STUDY DESIGN: Anti-HAV serology results recorded over 22 months were analysed. Equivocal and positive Architect anti-HAV IgM results were matched with available clinical and demographical data to identify confirmed and probable cases of acute HAV infection. RESULTS: Reactive anti-HAV IgM results were recorded for 88/7661 (1.15%) samples. Using clinical and laboratory data, 35 patients were confirmed to have acute HAV infection. Acute HA was associated with a mean Architect anti-HAV IgM value of 9.4 (SD 6.8-12.0). Cases of HA had a mean peak ALT value of 1920 (SD 682-3158). All confirmed cases (35/35) of acute HAV were associated with at least one clinical indicator, with 28/31 cases (90%) having a documented jaundice. All 35 (100%) cases of acute HAV infection had anti-HAV IgM > 4.0. A diagnosis other than acute HA was identified in 7/11 (63.6%) of low-level reactive anti-HAV IgM results (clinical data unavailable for further 4/11, 36.3%). Where clinical information was available, acute HA was excluded in all 31 patients with equivocal or low-level reactive anti-HAV IgM results. CONCLUSIONS: The accuracy of reports sent out to the clinician showed room for improvement. An interpretive algorithm is proposed including a clinically significant cut-off value for anti-HAV IgM.

[Extra hepatic manifestations of hepatitis A]. / Les manifestations extra-hépatiques de l'hépatite A.

Viral hepatitis A is characterized by a wide range of clinical pictures ranging from a completely unapparent infection to a fulminant, potentially fatal hepatitis or the classical icteric form. Hepatitis A can develop in an unusual way and extrahepatic manifestations (neurological, renal, haematological, cholecystitis, acute pancreatitis, vasculitis, etc.) can occasionally complicate the course of the disease. Although hepatitis A infection was identified in the early 1970s, there are few or no studies assessing the actual frequency of these complications. They have been studied mainly through clinical case reports. Currently, since the disease has become more common in adults, these complications are being increasingly observed. We present an update on extrahepatic complications during hepatitis A, which should be known by both specialist doctors (infectiologists internists, hepatologists and others) and general practitioners.